JP 2002-188993A discloses a particle analyzer that analyzes particles in urine by flow cytometry. The particle analyzer described in JP 2002-188993A feeds a sample solution containing particles into a sheath flow cell. The particle analyzer irradiates the sheath flow cell with laser light and detects the photo-detection signals from particles. The particle analyzer classifies the particles in urine into a population that includes casts containing inclusions, epithelial cells, and close-passing white blood cells and another population based on the difference integrated value of the signal waveform of the photo-detection signals and the peak level. The particle analyzer classifies casts, epithelial cells, and close-passing white blood cells based on the pulse width of the photo-detection signals.
Atypical cells may be contained in the urine in patients with urinary tract cancer. The atypical cells which are malignant cells or cells suspected of malignancy mean cells with atypicality, such as increased nuclei due to an increase in the amount of nucleic acids or increased chromatin content. Clinically, detection of the atypical cells in the urine is very important for early detection of renal disease and urinary tract cancer.
JP 2002-188993A does not describe detecting atypical cells in urine distinguishably from other formed elements in urine.